The present invention relates to a continuity test apparatus, and more particularly to a continuity test apparatus wherein the applied test voltage is less than one volt.
The design of some electron guns for use in conventional color television picture tubes incorporate electrodes, some of which are fabricated in parts which are subsequently welded together. For example, a first accelerating and focusing electrode might comprise two rectangular shaped cups which are welded together at their open ends in order to maintain good electrical contact therebetween.
It has been found in the past that the use of a conventional continuity tester would occasionally yield erroneous indications of continuity because the test voltage applied was too high. For example, when measuring continuity between the two cups which form the first accelerating and focusing electrode, the application of even a few volts between the two cups was sometimes sufficient to "bridge the gap" thereby giving a false indication of continuity on unwelded assemblies. In other words, this equipment had a terminal voltage which would give false reading of electrical continuity on unwelded electrodes which were merely in close physical contact.